Combination packer and tubing anchor



July 28, 1959 J. E. REED 2,896,725

COMBINATION PACKER AND TUBING ANCHOR Filed r ov. 19, 1956 Z'Sheets-Sheet 2 mm as me e N Wm H r COMBINATION PACKER TUBING ANCHOR John E. Reed, Santa Maria, Calif.

Application November 19, 1956, Serial No. 623,011

1 Claim. (Cl. 166216) 'This invention relates to combination packers and tubing anchors, and included in the objects of this invention are:

k ted States Patent First, to provide a combination packer and tubing anchor which is adapted to be lowered on a tubing string and set by manipulation of the tubing string, so as to engage the surrounding casing and permit the tubing string to be placed under a predetermined tension, thereby to minimize breathing of the tubing, and on being set, :to pack off the'annulus between the casing and the tubing string.

Second, -to provide in a well tool of this type an upwardly wedging slip construction and a novel means,

whereby, after the well tool is set a predetermined excess tension applied to the tubing string releases the well tool for ready removal.

With the above and other objects in view, as may appear hereinafter, reference is directed to the accompanying drawings in which:

Figure l is a side view of the combination packer and tubing anchor shown in its initial condition during movement into a well bore with its mandrel and tail pipe shown fragmentarily;

Fig. 2 is a similar side view, showing the parts of the device as they appear when set within a well casing, the surrounding casing being shown fragmentarily;

Fig. 3 is another side view, showing the position of the parts of the combination packer and tubing anchor during withdrawal from the well bore;

Fig. 4 is an enlarged transverse sectional view through 4-4 of Fig. 1;

Fig. 5 is an enlarged fragmentary longitudinal, partial sectional, partial elevational view taken through 5-5 of Fig. 4, showing particularly the slip and slip expander construction;

Fig. 6 is an enlarged fragmentary, longitudinal, sectional view taken through 66 of Fig. 1;

Figs. 7, 8, and 9 are transverse sectional views, taken respectively through 7-7, 88, and 99 of Fig. 5.

The combination packer and tubing anchor is mounted on a tubular mandrel 1, the upper end of which is attached to a tubing string, not shown. The lower end of the mandrel is attached by a coupling 2 to a tail pipe 3.

Fitted over the coupling 2 and lower portion of the mandrel 1 is a sleeve 4, the lower end of which is initially secured to the coupling 2 by means of shear pins 5. The upper end of the sleeve 4 forms an abutment shoulder 6 which is engaged by the lower end of a cylindrical packer sleeve 7. The upper end of the packer sleeve bears against an end ring 8.

Above the end ring 8 is mounted a slip 9 which extends upwardly along one side of the mandrel 1. The lower end of the slip 9 is provided with a collar 10 which fits loosely on the mandrel 1 above the end ring 8. The external surface of the slip 9 is preferably smooth. The lower portion of the inner side of the slip 9 confronting the mandrel 1 defines a fragment of a cylindrical surface .parallel with the outer mandrel surface, and the upper 2,896,725 Patented July 28, 1959 ICC portion of the inner side of the slip has a cylindric surface which diverges upwardly therefrom. This upwardly divergent surface is provided with radially extending key ribs 11.

Secured to the mandrel 1 above the collar 10 is an arcuate collar 12 which limits upward movement of the slip 9. Slidably mounted on the mandrel 1 above the arcuate collar 12 is a slip expander body 13 having a cylindric guide face 14 diverging upwardly from the axis of mandrel 1 and conforming to the upper inner diverging surface of the slip 9. The guide face 14 is provided with key slots which receive the key ribs 11 so as to hold the slip 9 against the guide face 14. The side of the slip expander body 13 opposite from the guide face 14 is provided with fixed bars 15 having teeth for engagement with a surrounding well casing.

The upper end of the slip expander body 13 is connected to a sleeve 16 slidably mounted on the mandrel 1 and having an external shoulder 17 at its upper end.

The upper end of the sleeve 16 journals within a retainer circumferential extremity. The mandrel 1 is provided with a key bar 24 permanently secured thereto and adapted to move in the key slot formed by the circumferentially extending portion 21, notch portion 22, and axial portion 23.

The upper end of the lower cage collar 20 is attached to cage springs 25 which extend upwardly and are attached at their upper ends to an upper cage collar 26 slidably mounted on the mandrel 1. The cage springs 25 are bowed and form with the cage collar 26 a cage structure which frictionally engages a surrounding Well casing designated C and shown in Fig. 2.

Operation of the combination packer and tubing anchor is as follows:

The parts of the combination packer and tubing anchor are initially disposed as shown in Fig. 1; that is, the key bar 24 is engaged in the notch portion 22 of the key slot and the shear pin 5 retains the sleeve 4 in its lower posi tion. The slip 9 is restrained against upward movement by the arcuate collar 12, and the slip expander body 13 is restrained against downward movement relative to the slip by the lower cage collar 20. However, by reason of the connection afforded between the sleeve 16 and retaining ring 18 the cage assembly can rotate relative to the slip'expander body 13 on the mandrel 1.

The device is lowered into the well bore to the desired depth, whereupon the tubing string is manipulated by pulling upwardly thereon to raise the key bar 24 clear of the notch 22, thereupon the tubing string is rotated and raised further so as to move the key bar into the axial portion 23 of the key slot, as shown in Fig. 2. This is made possible by the fact that the cage assembly tends to remain fixed in position by reason of frictional engagement with the surrounding casing.

Movement of the key bar 24 in the axial portion 23 of the key slot permits the slip 9 to move upwardly relative to the slip expander body 13. The slip wedges between the slip expander body and the surrounding casing, limiting its upward movement. Continued upward tension on the tubing string and mandrel 1 axially compresses the packing sleeve 7 so as to radially expand the sleeve against the surrounding casing and seal the annulus between the mandrel and the casing. Once the combination packer and tubing anchor is secured in position, a predetermined additional strain is applied to the tubing string so that thettubing string is maintained in tension, and the .lower end is prevented from breathing ormoving with the changes inload imposed by a pump installed within the lower end of the tubing string.

Normally, to return the-combination packer and tubing anchor to the position shown in Fig. 1 merely involves reversing the manipulation; that is, the key bar 24 is moved downwardly in the axial slot 23, then turned to thelatching position shown in Fig. 1.

However, should the tubing string be stuck, thensufiicient additional tension is applied to the shear pins 5, whereupon the mandrel 1 may move upward-1y causing the arcuate collar 12 to engage the underside of the slip expander body 13 and lift the slip expander body relative to the slip so as to free the slip, as shown in Fig. 3. This also relieves the compression-load on the packer so that it may contract and permit the entire assembly to be removed with the tubing string.

It should be observed that the packing sleeve may be omitted and a metal collar-substituted, if it is not desired v to packofi between the tubing and casing. This is sometimes desirable to permit escape of gases between the tubing string and casing which might'otherwise cause the well pump to gas lock.

While a particular embodiment of this invention has been shown and described, it is not intended to limit the same to the exact details of the construction set forth, and it embraces such changes, modifications, and equivalents of the parts and their formation and arrangement as come within the purview of the appended claim.

What is claimed is:

A tubing anchor, comprising: a tubular mandrel adapted to be connected to the lower end of a tubing string; a slip expander including an upwardly diverging expander face, said slip expander being slidable on said mandrel and having an initially upper position and a lowerjpositionon said mandrel; a slip axially slidable on said mandrel and divergently slidable relative to said mandrel axis on said expander face between a lower laterally retracted and an upper laterally expanded position relative to said slip expander; releasable means for fixing said slip in an initially upper position on said mandrel whereby on movement of said slip expander from its upper to its lower position relative to said mandrel said slip is forced upwardly along said divergent expander face against a surrounding casing to secure said mandrel and tubing string thereto; said vreleasable means including a collar on said mandrel a shear element extending through said collar into said mandrel, said element being shearable upon application of predetermined tension on said tubing string while said slip is wedged against said casing thereby to release said slip for movement to a lower retracted position relative to said slip expander, thereby to permit withdrawal of said tubing stnn'g and said tubing anchor from said casing.

References Cited in the file of this patent UNITED STATES PATENTS 

